Hi,
SF / FS are few MOSFET corners to check the behavior of the circuit when NMOS and PMOS have different strengths, like for SF - Slow NMOS, Fast PMOS; FS - Fast NMOS, Slow PMOS.
Monte Carlo simulation gives the effect of mismatch between two identical transistors (like input pair of differential opamp or current mirror transistors), due to variations in their "W" and "Vth" occurring during fabrication process. Here you have to select the transistors for which you wish to see the mismatch effect.
cinch